“The loosely knit coalition of groups has already targeted some of the Republican Party’s most established candidates, accusing them of compromising their conservative principles in negotiating with Democrats.

One of the most recent, high-profile Tea Party challenges is in South Carolina, where Nancy Mace, the first female graduate of The Citadel, is trying to unseat two-term Republican Sen. Lindsey Graham, whose efforts to pass immigration-reform legislation appears most upsetting to the movement.

Graham also frustrated conservatives so much this spring when criticizing fellow Republican and Kentucky Sen. Rand Paul for filibustering over the Obama administration’s drone strikes that FreedomWorks President Matt Kibbe said Graham was “begging for a primary.””